Micro system and manufacturing method

Abstract

The present disclosure provides a method for use in manufacturing a microsystem, the method comprising forming an array of pillars in a thickness of a substrate, an area surrounding the array of pillars defining a cavity in the substrate; transforming at least some of the pillars into a sacrificial material; and depositing a sacrificial material layer using a non-conformal deposition process to fill up the cavity while enclosing hollow channels between the pillars of the pillars array, thereby obtaining a cavity filled with an etching facilitator arrangement.

1 - 15 . (canceled) 
     
     
         16 . A method for use in manufacturing a microsystem, the method comprising:
 (a) forming an array of pillars in a thickness of a substrate, a volume enclosing the array of pillars defining a cavity in the substrate;   (b) transforming at least some of the pillars into a sacrificial material;   (c) depositing a sacrificial material layer using a non-conformal deposition process to fill up the cavity while encasing hollow channels between the transformed pillars of the pillars array, thereby obtaining a cavity filled with an etching facilitator arrangement.   
     
     
         17 . The method according to  claim 16 , wherein forming the array of pillars in a thickness of a substrate comprises:
 i) patterning the substrate to form a mask layer defining an array of features;   ii) etching the patterned substrate around said features to form the pillars array beneath the features array and the cavity surrounding the pillars array, the cavity including a mesh of trenches between the pillars of the pillars array.   
     
     
         18 . The method according to  claim 17 , wherein the mask layer further includes a cavity outline and the array of features is within said cavity outline. 
     
     
         19 . The method according to  claim 16 , wherein at least some of the features in the features array have a shape of a stem including at least one arm extending outwards. 
     
     
         20 . The method according to  claim 16 , wherein at least some of the features in the features array have a shape of a stem with at least three arms extending outwards. 
     
     
         21 . The method according to  claim 16 , wherein transforming at least some of the pillars into a sacrificial material includes fully transforming each pillar of the pillars array into sacrificial material. 
     
     
         22 . The method according to  claim 16 , wherein transforming at least some of the pillars into a sacrificial material includes partially transforming one or more pillars of the pillars array into sacrificial material. 
     
     
         23 . The method according to  claim 16 , wherein at least some of the hollow channels are interconnected in at least one network of interconnected channels. 
     
     
         24 . The method according to  claim 16 , wherein at least one hollow channel is not connected with the other hollow channels. 
     
     
         25 . The method according to  claim 16 , wherein the substrate being made of silicon, the step of transforming into a sacrificial material includes an oxidation process and the non-conformal sacrificial material layer deposition includes a non-conformal silicon-dioxide layer deposition. 
     
     
         26 . A method of manufacturing a micro-electro-mechanical system (MEMS) device comprising at least one suspended MEMS structure, the method comprising:
 I. forming a substrate with a cavity filled with an etching facilitator arrangement according to any of the preceding claims;   II. forming by micromachining the at least one MEMS structure above the at least one cavity filled with the etching facilitator arrangement, said at least one MEMS structure including one or more pathways therethrough providing access to the etching facilitator arrangement;   III. etching through said one or more pathways to reach the hollow channels so as to spread an etchant material through the channels and remove the sacrificial material from the filled cavity, thereby suspending the at least one MEMS structure over the cavity.   
     
     
         27 . The method according to  claim 26 , further comprising (IV) depositing one or more additional sacrificial layers to fill the one or more pathways in the MEMS structure. 
     
     
         28 . A micro-electro-mechanical system (MEMS) device obtained by the method according to  claim 26 . 
     
     
         29 . The micro-electro-mechanical system (MEMS) device of  claim 28 , wherein the MEMS device is a sensor or an actuator such as a speaker. 
     
     
         30 . A device for use in MEMS manufacturing including:
 (a) a substrate;   (b) a cavity formed within a thickness of the substrate,   
       wherein said cavity comprises a pillars array made of sacrificial material, said pillars array having been deposited with a non-conformal layer of sacrificial material to fill said cavity while embedding one or more hollow channels between the pillars of the pillars array.